Pump provided with exaust valve device and hemodynamometer incorporating the same

Abstract

A diaphragm is provided in a pump case so as to define a pump chamber communicated with an external member having an air chamber. An exhaust valve exhausts air in the pump chamber to lower a pressure in the air chamber, the exhaust valve being provided in the pump case.

1 . A pump, comprising: 
 a pump case;    a diaphragm, provided in the pump case so as to define a pump chamber communicated with an external member having an air chamber; and    an exhaust valve, which exhausts air in the pump chamber to lower a pressure in the air chamber, the exhaust valve being provided in the pump case.    
   
   
       2 . The pump as set forth in  claim 1 , wherein the exhaust valve composes a first exhaust valve which exhausts the air in the pump chamber at a constant first exhausting rate.  
   
   
       3 . The pump as set forth in  claim 2 , wherein the exhaust valve further comprises a second exhaust valve which exhausts the air in the pump chamber at a second exhausting rate which is higher than the first exhausting rate.  
   
   
       4 . The pump as set forth in  claim 1 , wherein at least a part of the exhaust valve is monolithically formed with the diaphragm.  
   
   
       5 . The pump a set forth in  claim 2 , wherein the first exhaust valve comprises: 
 a valve body, formed with a silt through which the air in the pump chamber is exhausted; and    a screw member, screwed into a first wall of the pump case to adjust an opening amount of the slit by a screwed amount thereof, thereby adjusting the first exhausting rate.    
   
   
       6 . The pump as set forth in  claim 3 , further comprising a motor, which actuates the diaphragm to introduce air into the pump chamber and to supply the introduced air to the air chamber, 
 wherein the second exhaust valve comprises: 
 a valve body; and  
 an actuator, which is driven by the motor to actuate the valve body so as to open or close an exhaust port communicated with the pump chamber.  
   
   
   
       7 . The pump as set forth in  claim 6 , wherein: 
 the actuator comprises: 
 a first gear, coupled with a rotary shaft of the motor;  
 a second gear, meshing with the first gear to be rotated;  
 a lever member, pivotably provided about the rotary shaft; and  
 a clutch mechanism, connecting the second gear and the lever member such that the lever member is pivoted in accordance with the rotation of the rotary shaft;  
   the lever member is pivoted in such a direction that the second gear is abutted against the valve body so that the valve body is moved so as to open the exhaust port, when the rotary shaft is rotated in a first direction; and    the lever member is pivoted in such a direction that the second gear is separated from the valve body so that the valve body is moved so as to close the exhaust port, when the rotary shaft is rotated in a second direction.    
   
   
       8 . A hemodynamometer, comprising: 
 a cuff, adapted to be attached on a patient body and having an air chamber; and    a pump, comprising: 
 a pump case;  
   a diaphragm, provided in the pump case so as to define a pump chamber communicated with the air chamber; and    an exhaust valve, which exhausts air in the pup chamber to lower a pressure in the air chamber, the exhaust valve being provided in the pump chamber.